case-insensitive strings

[gavinking]

I think it would be interesting to have built-in support for some sort of case-insensitive string type, where:

• dirty checking would use equalsIgnoreCase()
• UKs in schema generation would use lower()
• = and < comparisons in HQL would use lower()
• perhaps, we would lowercase the string before sending it to JDBC.

The idea came to me here jakartaee/persistence#209 (comment).

[beikov]

I love the idea. It's useful for e.g. Email addresses and domain names which are all case insensitive. In the past I used a PostgreSQL type called citext for this, but I think if we have a dedicated JavaType for this, that would be very useful.

[gavinking]

Well, hell, if some dbs have a type for it, we could even look into supporting that in DDL generation. That would be nice.

[beikov]

Dunno if we really should emit that DDL type by default. There seem to be some caveats with the built-in type: https://www.postgresql.org/docs/current/citext.html

I guess that should be configurable. Maybe we should consider some @Text annotation that also allows specifying this and optionally also the collation to be used?

[gavinking]

Ah OK, if it's a doubtful thing then no, better to stick to standard SQL types. TBH I had never heard of it before.